The present invention is directed to a lock box that is thermally insulated to permit medical samples, and the like, to be securely and safely stored for pickup for periods of 8 hours and more. More particularly, the present invention is directed to a lock box equipped with a failsafe lock which will not permit the key to be removed unless the lock elements are securely engaged.
Medical storage boxes have been produced by the assignee of the present invention, and others, for some time. These boxes are used for storing medical samples (blood, urine, etc.) for limited periods of time outside the offices to provide a courier from an analysis lab, for example, after-hour access to pick up the samples. Legislation approved by the California Senate (Senate Bill #765) requires reporting of any incidents of unlocked specimen boxes. It is therefore desirable to provide a failsafe lock mechanism in which the key cannot be removed from the lock unless the lock elements are properly engaged. In addition, it is desirable to provide a lock box which can store frozen samples for periods of 16 hours at temperatures below 30xc2x0 F., as low as 5xc2x0 F. Lastly, the styrene (or styrofoam) insulation used to line the lock box is subject to abuse as a result of insertion and removal of the stored items. It is therefore desirable to provide a separable liner which can be removed and replaced should the inner liner become worn, soiled or damaged.
The present invention addresses these concerns by providing a storage box for heat-sensitive sample containers comprising a generally rectangular enclosure defined by an outer peripheral wall of rigid material, said enclosure having four lateral walls, a bottom wall and a top wall which is pivotally attached to one of said four lateral walls; at least one layer of insulation lining an inner portion of each of said four lateral walls, said bottom wall and said top wall; a fail-safe, key-operated lock having a first member associated with said top wall and a second member associated with a second one of said lateral walls, said lock precluding a key from being removed from said lock unless said first member and said second member are in interlocking engagement; whereby said sample containers may be locked in said storage box with at least one freezable packet, said insulation having sufficient thickness to maintain a temperature of the heat-sensitive sample containers below a desired maximum temperature for at least eight hours regardless of an ambient temperature surrounding said box. The rigid material making up the outer peripheral wall is preferably sheet metal that is coated with a protective coating such as an enamel paint. Further, it is preferred that the box has adequate interior volume to accommodate at least one soft-sided, insulated satchel that can be removed with their refrigerated contents. The innermost liner of styrene is held in by a fiction fit and may be easily removed and replaced in the event of wear, soiling or damage.
The failsafe lock preferably comprises a cam cylinder associated with a first one of said top wall and said second lateral wall, said cam cylinder having a first latching means attached thereto and being operable by said key, said cam cylinder being oscillatable by said key between a first latched position and a second unlatched position; a second latch means associated with another of said top wall and said second lateral wall; a spring associated with the same one of said top wall and said second lateral wall as said cam cylinder and engaging a portion of said cam cylinder disabling its rotation to a position where said key could be removed therefrom; a push bar associated with said another one of said top wall and said second lateral wall for engaging said spring and moving it to a non-disabling position when said second latch means is positioned where it can be engaged by said first latch means; whereby said cam cylinder can only be rotated to a key-removable position when said top wall is closed so that said second latch means can be engaged by said first latch means. While this lock has been designed for use with a medical sample lock box, it will have general utility with other applications where it is desirable to ensure securement of a lock prior to withdrawal of a key.
Various other features, advantages and characteristics of the present invention will become apparent to one of ordinary skill in the art after a reading of the following specification.